Practise Practise

Practice is a noun meaning a habitual action or performance. It can also mean a repeated activity undertaken in order to improve a skill. It is also used to talk about an action as opposed to theory. The offices of a doctor, and lawyer, for example, are also called a practice. (US spelling)
Playing the piano well requires a lot of practice.

Practise as a verb means to perform habitually, or carry out an action, or to do repeatedly as an exercise to improve a skill. As practised, it means experienced or expert (UK spelling)
He was a Catholic, but didn't practise his religion.

Who is this cheeky monkey who dares to correct the Queen of Corrections ?  Off with his head !